1. Field of the Invention
The present invention relates to printing by means of an aerosol or mist of particles, and more particularly to printing with jets of aerosol ink particles.
2. DESCRIPTION OF THE PRIOR ART
Various techniques exist in the prior art for controlling the application of deposition of a cloud or mist of fine particles to a desired surface. Typically, such applications are used for printing, copying, coating, plating, reproducing, and the like. Generally, these techniques involve some form of electrostatic control wherein the particles of the cloud or mist are charged, and the passage of the charged particles to the desired surface is controlled, for example, by selective field deflection or precipitation of the particles out of the path to the intended surface. In other arrangements, selective application or deposition of particles is effected by electrostatic control of apertures leading to the intended surface by blocking or nonblocking fields thereacross.
According to one technique disclosed in U.S. Pat. Nos. 2,573,143 and 2,577,894 issued to C. W. Jacob, ink is atomized and carried as a mist in an air stream which passes a corona electrode where the ink particles are charged. The charged ink particles are then passed through a duct in a precipitating unit where an electrical field causes the charged particles to be precipitated on one side of the passageway. The number of particles deflected from the stream depends on the magnitude of the electrical field signal, thereby controlling the amount of ink deposited on the recording medium located opposite the orifice of the duct.